In the copulative cycle, the first, mental stage first appears. Its beginning is the emergence of sexual dominance. A characteristic feature of this stage is the awareness of sexual desire directed at a specific sexual object. And the sexual dominant directs behavior to master this object, and is the physiological basis of this stage.

In the mental stage, a man’s sexual behavior is manifested in such a way as to incline a sexual object to intimacy. To achieve this goal, speech exposure (affectionate words, persuasion) is used, which is then reinforced by touch and irritation of various erogenous zones (hugs, kisses, affection).

If the copulative cycle unfolds without obstacles, then the nervous excitement gradually increases, and at some point an erection occurs. This is the second erection stage. When the erect penis is inserted into the vagina (this is called introjection), copulative frictions begin (that is, translational movements of the penis into the vagina). This is the third, copulative, or frictional stage. The intensity of nervous excitement increases, then, due to the continued summation of frictions, the severity of sexual arousal, which coincides with ejaculation, sharply increases – this is the stage of ejaculation. Following this, a decrease in nervous excitement occurs. The refractory stage of the copulative cycle is approaching.

During the refractory stage, the substages of absolute and relative non-excitability are distinguished.

Some men are able to have repeated sexual intercourse without removing the penis after the first ejaculation. But in most men of mature age after ejaculation, a period of absolute sexual excitability sets in. In this period, no effect can cause an erection. After an orgasm for a certain time, a man is indifferent to the erotic and sexual actions of his partner, and if left alone, most often he simply falls asleep.

But if the partner does not allow the man to fall asleep, then after the absolute sexual excitability, a period of relative sexual excitability begins. Here it is already possible to cause an erection in a man, but for this the partner needs to make maximum efforts, since excitation is possible only under the influence of intensive stimulation of erogenous zones.

The relationship between the stages and the onset of a new stage of the copulative cycle is determined by the law of summation of irritations.

In the mental stage, an individual stimulus (for example, olfactory or auditory) is most often not able to cause an erection. And the summation of individual irritations (olfactory, auditory, visual, and touch – touch), interacting with neurohumoral irritations (nervous system and sex hormones), gradually increasing, reaches the threshold of the spinal cord erection center and causes an erection.

If any interference occurs, and the action of these stimuli stops or stops, then the erection weakens and then disappears.

Further, after the introduction of the penis into the vagina, the summation of individual irritations as a result of frictions reaches the threshold of the ejaculatory center and causes ejaculation and orgasm.

Here, too, if summation of irritations does not occur, for example, a man stops frictions or removes the penis, then, accordingly, there will be no ejaculation and orgasm.

A sexologist writes: “Sexual potency is a clear measure of self-awareness and self-confidence for most men. She reacts like a seismograph to fluctuations and changes in the environment and, above all, when a man’s self-worthiness is insufficient or labile (changeable – author’s comment). This explains the almost stereotypical appearance and occurrence of potency disorders, which in this regard are simultaneously a diagnostic criterion for psychogenic impotence: an erection decreases before immission, during or immediately after it; for some, this happens in preparation for sexual intercourse, for others only with the thought of impending intercourse, and for others – immediately after immission. While in a healthy man, an erection increases as the desired sexual intercourse approaches and in the preparatory period, in men with psychogenic impotence, the erection disappears. Outside of situations related to sexual intimacy, erections in these people are quite normal. ”